This invention relates generally to the field of airborne vehicles having deployable wings or fins, and more particularly to a vehicle having a deployable wing with a control surface, and specifically to an airborne vehicle having both a deployable wing and a control surface that are operated by a single drive mechanism.
It is known that the performance of an airborne vehicle, such as a missile, artillery shell or other projectile can be improved by the use of one or more fins or wings deployed along the longitudinal axis of the airborne vehicle. Such fins are used to improve the stability of the vehicle during its flight as well as to provide a steering mechanism to improve the targeting accuracy of the vehicle. In many instances it is necessary to store the fins within the body of the vehicle before deployment. The conventional method for doing so is to pivot the fin at one end and to deploy it radially outward after the vehicle is launched. The energy to deploy such a fin may be supplied by a motor or solenoid, a spring, a pressurized fluid or gas cylinder, or the aerodynamic force of the air passing over the vehicle during its flight. Drive mechanisms for such applications are often expensive to design and to manufacture because they are required to survive severe acceleration loads during the launching of the vehicle.
Certain designs for airborne vehicles require the use of both a lifting airfoil as well as a control surface associated with the airfoil. The mechanism used to deploy such an airfoil/control surface assembly and to control the assembly once it is deployed can be expensive, heavy and large, thereby limiting the size of airborne vehicle upon which it may be utilized. It is known, for instance, to utilize one motor for the deployment of a fin or wing, and a second motor for control of that fin or wing or a control surface associated therewith. The use of redundant motors adds to the expense, weight and size of such a design.
U.S. Pat. No. 5,108,051 issued on Apr. 28, 1992 to Montet et al. teaches a mechanism for deployment and control of an airborne vehicle fin that utilizes a single motor. A single actuator is utilized to rotate a fin from a first position in line with the axis of flight of the airborne vehicle to a second position perpendicular to the direction of flight. The aerodynamic forces acting on the fin are then utilized to cause the fin to pivot about a second axis so that it becomes aligned with the axis of rotation of the actuator. Thereafter operation of the actuator will perform a steering function by causing the deployed fin to pivot about its first axis. This system provides the advantage of utilizing only one actuator, however, it is limited in its application due to its reliance on the use of aerodynamic forces, as well as being limited by providing actuating forces along only a single axis. What is needed is a deployment mechanism for an airborne vehicle that can provide deployment and control forces along a plurality of axes without the need for a plurality of actuators.
Therefore, it is an object of this invention to provide an airborne vehicle having a deployable wing and an associated control surface that can be deployed and controlled by a single drive mechanism. It is a further object of this invention to provide an airborne vehicle having an airfoil which can be deployed from a storage to an extended position and can thereafter be controlled as a control surface by a simple, light, and relatively inexpensive deployment and control mechanism.